The invention relates to 1,3,4-thiadiazole-2-carboxylic acid derivatives.
Compounds for use against phytopathogenic fungi are already known. Compounds in use of this kind are for instance manganeseethylene-bisdithiocarbamate (U.S. Pat. No. 2,504,404), N-trichloromethylmercaptotetrahydro-phthalimide and N-trichloromethylmercapto-phthalimide (U.S. Pat. No. 2,553,770, U.S. Pat. No. 2,553,771, U.S. Pat. No. 2,553,776), tetrachloroisophthalodinitrile (U.S. Pat. No. 3,290,353, U.S. Pat. No. 3,331,735) as well as mercury-organic compositions.
Agents for simultaneous use against nematodes and pathogenic soil fungi are likewise known, for instance sodium N-methyldithiocarbamate (British Pat. No. 789,690).
The object of the present invention is to provide agents of superior activity or other superior properties which have simultaneously fungicidal and nematocidal effects.